Multilayer, co-extruded, ionomeric decorative surfacing

ABSTRACT

Decorative ionomeric surfaced film and sheet (e.g., multilayer co-extruded polymer) and articles made therefrom (e.g., automotive panels and parts) exhibiting good weatherability, mar resistance, and surface appearance of a high quality automotive finish (including color, haze, gloss, and DOI) and economical process for making (e.g., co-extrusion) and using (e.g., thermoforming and injection backfilling) the same.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] Applicant claims the benefit of priority to provisionalapplication 60/197,275 filed Apr. 14, 2000, herein incorporated byreference.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention relates to multilayer, co-extruded,ionomeric thermoplastic sheet and film, articles manufactured with adecorative surface of such sheet and film, and processes for makingshaped articles having a top surface of decorative ionomeric film.

[0004] 2. Description of the Related Art

[0005] To describe the background of the present invention in thissection and various components used in the invention, various patentsare referenced. Each of these patents is incorporated herein byreference.

[0006] There is an increasing need, particularly in the automotiveindustry, for panels and parts made of polymer materials. Use of suchpolymer panels and parts provide numerous benefits. For example, weightof the finished assembly is reduced (important for automobiles), capitalcosts associated with plastic are lower than with metal, styling freedomis increased (important in automotive industry where there are more andmore model demands), and manufacturing (plastic tooling) costs arelowered.

[0007] Use of such parts and panels, however, has been limited byvarious problems. Typically, polymer surfaced panels do not present asurface appearance comparable to a high quality automobile finish or donot provide a good bonding surface for the paints needed to achieve thehigh quality finish. Furthermore, high quality painting can be costlyand present significant environmental, as well as safety and healthproblems, particularly those associated with volatile organic carriersused in paints. Other concerns with polymer parts include suitableproperties and durability of those properties with extended outdoorexposure, including high gloss appearance, impact strength, hightemperature properties (e.g. tensile strength and dimensionalstability), low temperature properties, durability, scratch and marresistance, and distortion of appearance at weld lines and with complexparts such as those made with deep draw. Attempts to solve theseproblems have met with mixed success.

[0008] Producing a surfacing film with paint like appearance hasexperienced limited success due to problems in processing films ontoarticles and unattractive economics for films in replacing paint.Fashioning a surfacing (skin) film system that can replace paintappearance is challenging since the film is required to meet manyspecifications including appearance that is similar to paint in bothsolid and metallic colors. In metallic paint application, a specialeffort must be made to control the size of the effect particles and theparticles' orientation in painted surfaces in order to exhibit thedesired metallic appearance. Flat or higher aspect ratio (length tothickness) effect particles in paint formulations are applied in ways toobtain a flat or parallel orientation with the surface. A variablecharacterizing this particle orientation in paint is called flop, and iscalculated from color measurements (L values) obtained at differentangles from the light source. Duplicating this metallic appearanceinexpensively with a polymer surface skin system that has the othernecessary surface attributes of high gloss, durability in outdoorexposure, chemical resistance, impact resistance, layer adhesion,temperature resistance and other properties has met very limited successbased on a very small decorated surface market share for plastic coloredskins.

[0009] Decorative composite surfacing films made from a liquid solventor dispersion system such as those disclosed in U.S. Pat. Nos.4,810,540; 4,931,324; 4,943,680; and 5,342,666 have been used. Dry painttransfer products such as those taught in U.S. Pat. No. 5,707,697 havebeen used. U.S. Pat. No. 5,985,079 teaches melt extrusion coating as azero-solvent approach to clear coat production and co-extrusion as anapproach to base coat/clear coat production for certain colors. EP 0 949120 A1 presents a flexible, weatherable decorative sheet material thathas an extruded base layer with a clear outer layer of extruded film asan overlay. A color adjustment layer of printing ink can be includedbetween the base layer and the clear coat.

[0010] Reissue of U.S. Pat. No. 5,514,427 (Re. 36,457) purports to solvethe problems presented by the PVC and films such as the Tedlar® filmsmarketed by E.I. du Pont de Nemours and Company through the use of asubstantially molecularly unoriented cast polymer film prepared byliquid casting methods. Typically these liquid cast films requiremultiple step processes to provide sheet attributes suitable forthermoforming and adhesion properties for injection cladding, as surfaceskins that provide a paint-like appearance. Often in these films, thepolymer, pigment and effect particles are cast onto a high gloss filmfrom a solution followed by solvent evaporation. In other filmconstructions, the pigment and effect particles may be printed onto thesurface in order to provide the desired metallic effect orientation andappearance such as provided by a paint. Often though these films are notcommercialized due to uneconomical cost in materials or processing ordeficient attributes such as appearance degradation after thermoformingdue to the thin pigment carrying layer or the thin pigment layerstreaking after elongation.

[0011] Another approach has been to make a “solid” part with molded-incolor. Bexloy®W automotive engineering resin, a blend of ionomer andpolyethylene sometimes reinforced by glass fiber, marketed by E.I. duPont de Nemours and Company, for instance, has found increasing use inmolded parts such as automobile bumpers. Solid color can be incorporatedinto the material, but success in incorporating metallic colors has beenlimited. Also, paint adherence to Bexloy®W resin is poor and paintapplication that requires use of high temperature paint baking ovens(Original Equipment Manufacturing “OEM” Painting) is not feasible sinceBexloy®W lacks suitable high temperature properties. To enhance marresistance, a light grain is typically applied to this materialresulting in a loss of “Distinctness of Image” (DOI), a key index usedto evaluate the perceived quality of an exterior finish in theautomotive industry.

[0012] Another “solid” material that has been used is Surlyn®Reflections Series® resins, an ionomer-polyamide blend, marketed by E.I.du Pont de Nemours and Company. Molded parts made from this engineeringmaterial retain important performance characteristics of the Bexloy®W,have high gloss exhibiting DOI's at least comparable to the best ofpaint finishes on smooth or “Class A” surfaces, particularly DOI's over80 and as high as 90 to 95. Solid and metallic colors can beincorporated and parts can be painted. High temperature properties aresufficient to permit OEM Painting without the need for special jigs orhangers to maintain part shape during the bake step. See U.S. Pat. No.5,866,658.

[0013] By molding in color, certain capital, operating, and pollutionabatement costs, particularly those associated with paint and solventsystems, can be eliminated. The solid parts have more durability andexhibit fewer defects as a result of weathering, chemical attack, andchipping than painted parts in use. However, they can exhibit splay,ghosting, flow lines and, in the case of a flake or particle with anaspect ratio, “metallic flow lines” which are often objectionable flowinduced visual imperfections that particles in the polymer highlight dueto light reflection and scatter. Solid injection molded parts can beuneconomical since the higher value polymer that provides the desiredsurface attributes is typically much thicker than needed to provide justthe attributes of the surface, and in many cases the entire thickness ofthe part may be the higher value polymer.

[0014] Japanese patent application (Kokai) No. SHO 58(1983)-155953,teaches the concept of making a laminated molding body with a polyolefinlayer and a surface layer made from a metal salt of anethylene-α,β-unsaturated carboxylic acid copolymer having a glossysurface after lamination. Although the reference teach generally thatthere are no special limitation on the method used for laminating thebase layer (polyolefin) to the surface layer (ionomer) with or withoutan intermediate adhesive layer which included co-extrusion, the workingexamples deal exclusively with hot pressing a commercial grade ionomerfilm (Surlyn®A1652) to a 2 mm thick polyolefin sheet of polypropylene orethylene-propylene block copolymer. Also, the fabrication of thecase-shaped product involved preheating the laminated sheet and vacuummolding on the side opposite the die. No mention of multilayer,co-extruded, ionomer film or sheet and any advantage of the same ispresent in this prior art reference.

BRIEF SUMMARY OF THE INVENTION

[0015] The present invention generally relates to a multilayer ionomericthermoplastic sheet (skin) for surfacing polymer parts (or othersubstrates including metal) to provide a high quality surfaceappearance, such as one suitable for interior or exterior automotiveparts, appliance panels, general aviation applications and the like. Thesheet exhibits a colored appearance similar to a surface which ispainted with a solid color or a color containing particles that providea “special effect” to the appearance often referred to as a metallicpaint appearance. The novel methods of fabricating a part according tothe instant invention using the decorative sheet involve both extrudedmonolayer and multilayer sheeting, particularly co-extruded, sheetshaving an ionomeric or ionomer-polyamide blend top surface layerco-extruded onto a selected second polymer layer. Shaped articles madeby thermoforming multilayer co-extruded ionomeric sheets (particularlythose having sufficient thickness to be self-supporting), and articlesformed by back-filling the decorative thermoplastic monolayer sheet orco-extruded sheet according to the methods of the instant invention havea high quality surface appearance comparable to a high qualityautomotive paint finish. The present invention also provides methods forforming shaped polymer articles with the decorative skin sheet on theouter surface thereof.

[0016] Among other features, the present invention allows reducedmanufacturing cost, reduced material costs, and appearance enhancementthrough controlled particle orientation and combination of materialclarity and translucent pigment use with effect particles. In oneembodiment, manufacturing of shaped articles can be accomplished infewer steps than conventional “dry paint film” by feeding the extrudedthermoplastic sheet of the present invention, preferably preheated,directly into an injection cladding mold for back-filling from a roll offlat sheet that hasn't been preformed. Sheeting of this inventionreduces surface imperfections such as ghosting, flow lines, and glassmarks, and metallic appearance problems associated with injection moldedparts. It overcomes the processing drawbacks of some fluoropolymercontaining skin films in deeper draw thermoforming such as streaking.The present invention allows great flexibility and improved economy inmaking parts with Class A surface by using backfill materials with thethermoformable surface sheet. Finished part properties and costs can betailored by varying the backfill material, by adding stiffening or othercomponents to the backfill material, by special processing of thebackfilling material (e.g., foaming) or by trim or off quality materialinclusion in the backfill material.

[0017] The decorative sheet of the present invention is a multilayersheet wherein the top layer of the multilayer sheet comprises an ionomeror ionomer-polyamide blend. The thermoformable sheet can be made in asheet multilayer melt extrusion process with pigment and flake particlesin the surface layer or other layers of the sheet extrusion process. Inthe case of an ionomer surfaced sheet construction, a patterned ordesigned film or sheet can be extrusion coated with or laminated to theionomer sheet with the design or pattern showing through.

[0018] The process for making sheet with the ionomer orionomer-polyamide blend surface layer overcomes deficiencies andeconomic constraints of existing polymer based “paint films”. Multilayersheet co-extrusion processing provides pigment carrying layers ofsufficient thickness that they maintain appearance and hiding powerfollowing deep draw thermoforming, control of machine direction effectparticle orientation to allow satisfactory replication of paintappearance and one step processing (excluding subsequent thermoforming,cladding, and/or trimming steps etc.) which improves the economics forcompetition with paint systems.

[0019] The shaped plastic article of the present invention has a highquality surface appearance comparable to a high quality automotive paintfinish. It can be a thermoformed sheet or a back-filled thermoplasticsheet.

[0020] Thus the present invention provides multilayer film or sheetcomprising:

[0021] a.) a first co-extruded polymeric layer consisting essentially ofionomer; and

[0022] b.) at least one co-extruded second polymeric layer selected fromthe group consisting of ionomer, ionomer-polyethylene blend, andionomer-polyamide blend in contact with the first co-extruded polymericlayer.

[0023] The present invention further provides a multi layer film orsheet comprising either:

[0024] a.) a first co-extruded polymeric layer consisting essentially ofionomer; and

[0025] b.) at least one co-extruded second polymeric layer consistingessentially of very low density polyethylene in contact with the firstco-extruded polymeric layer; or

[0026] a.) a first co-extruded polymeric layer consisting essentially ofionomer; and

[0027] b.) at least one co-extruded second polymeric sheet layerconsisting essentially of ethylene polar copolymer in contact with thefirst co-extruded polymeric layer; or

[0028] a.) a first co-extrusion polymeric layer consisting essentiallyof ionomer-polyamide blend; and

[0029] b.) at least one additional co-extruded second polymeric layer incontact with the first co-extrude polymeric layer.

[0030] In each of the above embodiments the multilayer film or sheet mayfurther comprise at least one additional co-extruded third polymericlayer in contact with the second co-extruded polymeric layer. Theethylene polar copolymer co-extruded second layer is preferably an acidfunctionalized copolymer when the top surface is an ionomer layer. Thesecond polymeric layer is preferably a maleic anhydride functionalizedpolymer when the top surface layer is an ionomer-polyamide blendco-extruded. Preferably one or more of the co-extruded polymeric layerscontain pigments, dyes, flakes, or mixtures thereof.

[0031] The ionomer preferably consists essentially of a copolymerderived from ethylene and α,β-ethenically unsaturated C₃ to C₈carboxylic acid wherein the copolymer is partially neutralized withmetal ions. The ionomer-polyamide blend consists essentially of one ormore polyamide which forms a continuous phase or co-continuous phasewith one or more ionomer dispersed therein, the ionomer is present inthe range from 60 to 40 weight percent and the polyamide is present inthe range from 40 to 60 weight percent based on the total weight ofionomer and polyamide, the ionomer consisting essentially of a copolymerderived from ethylene and α,β-ethenically unsaturated C₃ to C₈carboxylic acid wherein the copolymer is partially neutralized withmetal ions; wherein the average acid content of copolymer prior toneutralization is present in a sufficiently high percentage such thatneutralization in the range of 55 to 100 mole percent of the acidpresent at melt temperature with one or more metal cations increases theviscosity of the ionomer above that of the polyamide.

[0032] The present invention further provides a process for makingshaped article having an ionomer or ionomer-polyamide blend as a topsurface comprising the steps of:

[0033] a.) positioning a monolayer sheet of ionomer or ionomer-polyamideblend or a multilayer co-extruded sheet into a mold, wherein thethickness of the monolayer sheet or the multilayer sheet is from 8 to 60mils and wherein the multilayer sheet comprises;

[0034] i.) a first co-extruded polymeric layer selected from the groupconsisting of ionomer and ionomer-polyamide blend; and

[0035] ii.) at least one additional co-extruded second polymeric layerin contact with the first co-extruded polymeric layer; and

[0036] b.) injection backfilling the monolayer sheet or multilayerco-extruded sheet with a suitable backfilling material.

[0037] Preferably the sheet is preheated prior to the injectionbackfilling particularly for thick sheet and sheet of higher meltingpoint ionomer-polyamide blends. In one embodiment of this process themultilayer sheet comprises;

[0038] (i) a first co-extruded polymeric layer consisting essentially ofionomer;

[0039] (ii) a second co-extruded polymeric layer selected from the groupconsisting of ionomer and ionomer-polyamide blend in contact with thefirst co-extrude polymeric layer; and

[0040] (iii) at least one additional co-extruded third polymeric layerin contact with the second co-extrude polymeric layer.

[0041] The present invention further provides a process for making athermoformed, multilayer, sheet-surfaced article comprising the stepsof:

[0042] a.) positioning a multilayer sheet into a mold, wherein thethickness of the multilayer sheet is from 8 to 60 mils and wherein themultilayer sheet comprises;

[0043] i.) a first co-extruded polymeric layer selected from the groupconsisting of ionomer and ionomer-polyamide blend; and

[0044] ii.) at least one additional co-extruded second polymeric layerin contact with the first co-extrude polymeric layer; and

[0045] b.) raising the temperature of the sheet sufficiently to softenthe multilayer sheet; and

[0046] c.) conforming the softened sheet to the contoured surface of asubstrate in the mold.

[0047] In one embodiment of this process the multilayer sheet comprises;

[0048] (iv) a first co-extruded polymeric layer consisting essentiallyof ionomer;

[0049] (v) a second co-extruded polymeric layer selected from the groupconsisting of ionomer and ionomer-polyamide blend in contact with thefirst co-extruded polymeric layer; and

[0050] (vi) at least one additional co-extruded third polymeric layer incontact with the second co-extrude polymeric layer.

[0051] Thus the present invention provides an article consistingessentially of a substrate to which a multilayer film or sheet isadhered, wherein the multilayer film or sheet comprises either:

[0052] a.) a first co-extruded polymeric layer consisting essentially ofionomer; and

[0053] b.) at least one co-extruded second polymeric layer selected fromthe group consisting of ionomer, ionomer-polyethylene blend, andionomer-polyamide blend in contact with the first co-extruded polymericlayer; or

[0054] a.) a first co-extruded polymeric layer consisting essentially ofionomer; and

[0055] b.) at least one co-extruded second polymeric consistingessentially of very low density polyethylene in contact with the firstco-extruded polymeric layer; or

[0056] a.) a first co-extruded polymeric layer consisting essentially ofionomer; and

[0057] b.) at least one co-extruded second polymeric sheet layerconsisting essentially of ethylene polar copolymer in contact with thefirst co-extruded polymeric layer; or

[0058] a.) a first co-extrusion polymeric layer consisting essentiallyof ionomer-polyamide blend; and

[0059] b.) at least one additional co-extruded second polymeric layer incontact with the first co-extrude polymeric layer.

DETAILED DESCRIPTION OF THE INVENTION

[0060] For purposes of this invention the following terms are to bedefined as follows:

[0061] 1. “Copolymer” means polymers containing two or more monomers andas such the term is intended to include both “bipolymer” and“terpolymer” as well as polymers produced from more than threecomonomers. The terms “bipolymer” and “terpolymer” mean polymerscontaining only two and three monomers respectively. The phrase“copolymer of various monomers” means a copolymer whose units arederived from the various monomers.

[0062] 2. “(Meth)acrylic acid” means acrylic acid and methacrylic acid,and the term “(meth)acrylate” means acrylate and methacrylate.

[0063] 3. “Consisting essentially of” means that the recited componentsare essential, while smaller amounts of other components may be presentto the extent that they do not detract from the operability of thepresent invention.

[0064] 4. “Distinctness of Image” (DOI) is a measure of the “crispness”or “degree of definition” of a reflection of a object in a coloredfinish compared to the actual object itself. (DOI) is defined in ASTMStandard-284 as: distinctness-of-image-gloss, n-aspect of glosscharacterized by the sharpness of images of objects produced byreflection at a surface. DOI can be measured with a BYK-Gardner Wavescandoi instrument bases on U.S. Pat. No. 1,155,558. In the automotiveindustry, satisfactory finishes on a smooth or “Class A” surfacetypically will have a finish with a DOI value of at least 60, preferably80 or higher.

[0065] 5. Flop is an expression and a calculated variable used todescribe or characterize appearance change with viewing angle. In itscalculated term context, it is calculated from color measurement Lvalues at 3 different angles from a light source. The higher the flopvalue, the greater the appearance change in viewing at different angles.

[0066] 6. Effect particle is a particle added to paints or pigmentswhich provides an appearance effect or change in color with view angle.Typical effect particles are aluminum flakes and mica particles. Ofteneffect particles are flat and thin and their orientation can beimportant in imparting a certain appearance.

[0067] 7. Machine direction (MD) means the orientation in a film whichis in the direction, either upstream or downstream, that the film isexiting the machine or die. The MD direction can be referred to aseither pointing into the machine or away from the machine, 180 degreesapart. The term can be associated with film length. This is in contrastto the cross machine direction or “TD” direction which is the direction90 degrees from the machine direction or exit flow direction andtypically indicates the direction across the film width from one side tothe other side.

[0068] 8. CIELAB color difference is defined in ASTM Standard-284 as,n-color difference calculated by using the CIE 1976 L*a*b* opponentcolor scales, based on applying a cube-root transformation to CIEtristimulus values X,Y,Z.

[0069] 9. Gloss is defined in ASTM Standard-284 as, n-angularselectivity of reflectance, involving surface reflected light,responsible for the degree to which reflected highlights or images ofobjects may be superimposed on a surface.

[0070] 10. Haze is defined in ASTM Standard 284 as: n-scattering oflight at the glossy surface of a specimen responsible for the apparentreduction in contrast of objects viewed by reflection from the surface.

[0071] 11. A Class A surface is a surface that by itself of when paintedresults in DOI, gloss and haze readings of 80, 90, 10.

[0072] It should be further appreciated that for purposed of the presentinvention, the use of the expressions multilayer film and the multilayersheet refer collectively to polymeric films and sheets that are fromabout 1 mil to about 60 mils thick. Although no single thicknessdimension is felt to represent a demarcation between film and sheet, forpurposes of this invention the use of the word sheet, in both theprocesses for making a shaped article involving backfilling of sheet andfor making a thermoformed article from sheet, refers to polymericmaterial of 8 to 60 mils thick.

Film Process

[0073] Lamination and melt extrusion processes known in the art can makethe thermoformable sheet of the present invention. Multilayer sheets canbe made on extrusion lines that may be configured and operated in waysknown in the art. The monolayer or multilayer sheets of the presentinvention may be laminated or coated as the surface layer onto othersubstrate sheets to form decorative sheet structures.

[0074] In a typical extrusion system, selected solid plastic particlesin pellet form are fed to an extruder, melted and plasticated, pumpedthrough a transfer pipe into a feedblock and then to an extrusion die ordirectly to a die. The molten curtain that exits the die is depositedonto a moving roller which transfers the solidifying polymer through agap or nip between two counter-rotating rollers to a third roller andsubsequently through another nip system between rollers which pulls thesheet through the take-off system. The sheet is subsequently rolled ontoa core creating a roll of sheet or the sheet can be cut to a length andstacked as flat sheets.

[0075] In a typical system for making multilayer sheet, there aremultiple extruders into which particles are fed, melted and plasticatedby the extruder screw and heated barrel system. The resulting moltenmass can be pumped through a transfer pipe into a co-extrusion feedblockfor the purpose of combining the flows into contacting layers. Thefeedblock can be equipped with a plug that can be changed to allowdifferent combinations of extruders and layers to be run on the line.The plug routes the flows within the feedblock and combines the layersprior to exiting the feedblock and going into an extrusion die. Theextrusion die has a flow area or manifold that widens and thins thesingle or multilayer melt flow into a thinner, wider web or meltcurtain. The multilayer molten flow is widened and thinned to the dieflow width and die gap opening.

[0076] The “match” in rheology between the layers will determine howwell the layers spread together in the die. If there is a significantdifference in flow properties, the layers may not all flow to the widthof the die. In this case, lower viscosity material may flow to the endof the die opening and higher viscosity material flow width will beless. If the layer flow properties are well matched, each layer willflow to the full width of the die. Finally, if the flow properties arepoorly matched, quality sheeting may not be produced due to flowinstabilities between layers in the die and air gap exit the die.

[0077] Alternatively, a different type of extrusion die, a multiplemanifold die, can be used in place of the “extrusion feed block andsingle manifold die” arrangement. In this case, separate extruder meltstreams flow directly into separate flow paths or manifolds within amultiple manifold die. Each layer in this case flows through its ownmanifold and is spread and thinned to the width of the die flow areaprior to the layers combining and flowing together into a multilayermolten sheet. The combination of layers in this case, occurs near thedie exit after each layer has been thinned and widened separately and istherefore less sensitive to mismatch in flow properties. In a similarfashion, more than 1 layer can be fed into a separate manifold where themultiple layers can be spread and thinned in the manifold.

[0078] The molten flow exits the die as a molten curtain and flows ontoa metal roller just prior to contacting a larger diameter roll. Theserolls are counter rotating. The gap between these rollers is set toprovide a uniform opening, referred to as a nip. The molten plasticcontacts both rolls as it is conveyed through the controlled openinggap. The roll arrangement provides a higher glossy finish on the sheetand more uniform thickness to the sheet. The primary roller is a highlypolished roll that is contacted by the sheet for approximately half ofits circumference prior to releasing the solidifying plastic typicallyto a third roll downstream in the takeoff roller system. The sheet issubsequently taken through another nip system between rollers whichpulls the sheet in the system. The sheet is subsequently rolled onto acore creating a roll of sheet or alternatively can be cut to length andstacked.

[0079] In practice, there are several alternatives for the molten flowexiting the die. For example, the die can be repositioned to drop themolten curtain so as to contact the larger roll initially just prior tothe nip. Another example arrangement positions the die at angles betweenvertical and horizontal to result in vertical or horizontal molten flowfrom the die. Also, instead of a second roll providing a nip, othermeans can be used to force the molten plastic onto a roll such as airflow pushing the molten web onto a roller.

Co-extrusion Sheet

[0080] The appearance of sheet from the sheet process can have severalvariables that effect its appearance and performance. The sheet can havea clear surface layer with under layers containing pigments and effectparticles in the case of the ionomer sheet or it can have a pigmentedsurface layer with or without effect particles as is the case with theionomer-polyamide blend. One or more of the under layers in either casemay contain pigment or particles.

[0081] The sheet appearance can be changed with the blend of pigmentsused and with the orientation of the effect particles if they arepresent. Ideally for solid color pigmentation only, the color would notchange based on viewing direction for a flat sheet if the purpose is tomatch a typical paint appearance surface. However, effect particles insheet extrusion encounter multi axial particle orientation that effectscolor and appearance. It has been found that orientation of the flakeparticles toward a particle that is closer to parallel with the surfacecan be controlled in sheet extrusion to a certain extent with the properequipment and operating techniques. This is necessary to provide acloser match to painted surfaces, to minimize color difference based onviewing direction and to minimize color differences between a pigmentedsheet product and a painted surface.

[0082] It has been found that flop value differences calculated fromcolor measurements in the upstream and downstream MD directions of asheet product could be minimized which in turn minimizes colordifferences based on viewing direction. A single manifold die with thegap opened to a significant degree provided flop difference values ofless than about 2 whereas when the die is run with a die gap openingconsidered more typical, flop values were approximately 4. The die doesnot have a short land length. On another die with 2 manifolds and ashort die land length, flop differences were found to be higher than 3at typical, low and high gap settings and not effected by gap. Based onthis preliminary limited data particle orientation characterized by flopcalculations, can be effected by a combination of both die gap and dieexit characteristics.

[0083] Metallic appearance can be effected through a combination oflayer inherent clarity, translucent pigments and effect particles usedin a layer which in combination allows flat metallic surfaces to be seenwith less light scattering and to a greater depth enhancing appearanceand accentuating the flop or change in appearance with viewing anglethat is a desirable attribute. To provide hiding power so undesirablelight reflection from underlying surfaces or layers are minimized, athick layer carrying the pigment and flake can be employed, or a higherconcentration of pigment and flake can be used or an under layer withpigment and/or flake can be utilized to effect appearance.

[0084] The combination of clear/color layers of either ionomer-ionomeror ionomer-acid copolymer as the first two layers in the sheet providethe desirable characteristics of the surface layer with mar resistance,high clarity, durable in outdoor exposure, chemical resistance and highgloss in combination with a second clear layer that has goodcompatibility for adhesion, minimum distortions from interfacedisturbances that can be caused be flow differences and appearanceattributes described above. In addition, ionomer over other layermaterials such as EVA's or E-acrylates or PE type materials may alsoprovide a satisfactory appearance system although these systems may notprovide the high levels of adhesion or the depth and distinctiveness ofmetallic particle reflection.

[0085] Additives that go into the appearance layers may requirecompatible carriers to minimize resultant haze that can be generated bymaterial incompatibility causing light refraction at the incompatibleinterface. Additives include pigment or effect particle carriers, UVadditive carriers or anti-static additive carriers. Compatible carriermaterials include ionomer, acid copolymer, EVA, E-acrylate copolymers orderivatives.

Thermoformable Skin

[0086] The thermoformable skin of the present invention has attributesthat can include good formability and release from tooling inthermoforming, excellent DOI, high gloss and low haze surfaceappearance, solid and metallic color appearance, good mar and scratchresistance, good weatherability, good impact resistance and goodchemical resistance. It may be formed into a weatherable, decorativesheet for surfacing polymer parts. The sheet is surfaced with an ionomeror ionomer-polyamide blend.

[0087] The ionomers and the ionomer-polyamide blends useful in thepresent invention are described below. The decorative sheet can bemonolayer or multilayer. When a multilayer, at least the top layer ofthe multilayer sheet is made from the ionomer or ionomer-polyamideblend.

[0088] The monolayer sheets preferably are about 1 to about 50,alternatively about 2 to about 20, mils thick. The multilayer sheetspreferably are about 8 to about 60, alternatively about 12 to about 40mils thick. However it should be appreciated that thicker dimension suchas 60 to 400 mils, alternatively 80 to 180, can be easily achieved andretain many of the benefits of the instant invention for thermoforminglarger parts requiring greater stiffness.

[0089] Multilayer skin films can be tailored to fit the needs of a widevariety of specific applications. For example, layers in the skinstructure can provide pigmented solid color, pearlescent pigment and/orother nacreous pigment for colored metallic appearance properties (seeU.S. Pat. No. 6,060,135 and in particular column 4, lines 25-40,incorporated herein by reference), stiffness for handling, thermoformingproperties, layer adhesion function and a back side layer which willadhere to a backfill material to form a shaped molded article.

[0090] Some typical skin constructions include (where slash markrepresents layer interface and parentheses designate additive):

[0091] Ionomer monolayer (clear or pigmented)

[0092] Ionomer-polyamide blend monolayer (pigmented)

[0093] Ionomer (clear)/polyethylene-ionomer blend (pigmented)

[0094] Ionomer (clear)/polyethylene-elastomer blend (pigmented)

[0095] Ionomer (clear)/ionomer (pigmented)/ethylene copolymer

[0096] Ionomer (clear)/ionomer (pigmented)/very low density polyethylene

[0097] Ionomer (clear)/ethylene acid copolymer (pigmented)/very lowdensity polyethylene (pigmented)

[0098] Ionomer (clear)/ethylene acid copolymer (pigmented)/very lowdensity polyethylene/olefinic thermoplastic

[0099] Ionomer (pigmented)/ionomer (pigmented)/ethylene acid copolymer

[0100] Ionomer (pigmented)/ethylene acid copolymer

[0101] Ionomer (pigmented)/terpolymer ethylene-acid-acrylate(pigmented)/olefinic thermoplastic

[0102] Ionomer (pigmented)/terpolymer ethylene-acrylate-glycidalmethacrylate (pigmented)/olefinic thermoplastic

[0103] Ionomer (clear)/terpolymer ethylene-acid-acrylate(pigmented)/olefinic thermoplastic

[0104] Ionomer (clear)/terpolymer ethylene-acrylate-glycidalmethacrylate (pigmented)/olefinic thermoplastic

[0105] Ionomer (clear)/ionomer (pigmented)/terpolymerethylene-acrylate-glycidal methacrylate/olefinic thermoplastic

[0106] Ionomer (clear)/ethylene-acrylate copolymer (pigmented)/ethylenecopolymer

[0107] Ionomer (clear)/ionomer (pigmented)/ethylenecopolymer/polyethylene

[0108] Ionomer (clear)/ionomer (pigmented)/ethylene copolymer/polyestercopolymer

[0109] Ionomer (clear)/ionomer (pigmented)/polyamide (pigmented)

[0110] Ionomer (clear)/ionomer (pigmented)/tie layer(pigmented)/thermoplastic polyolefin

[0111] Ionomer (clear)/ionomer (pigmented)/tie layer/thermoplasticpolyolefin (pigmented)

[0112] Ionomer (clear)/ionomer (pigmented)/polyethylene-ionomer blend

[0113] Ionomer (clear)/ionomer (pigmented)/tie/nitrile copolymer

[0114] Ionomer-polyamide blend/tie/thermoplastic polyolefin

[0115] Ionomer-polyamide blend/tie/polyester copolymer

[0116] Ionomer-polyamide blend/tie/nitrile copolymer

[0117] Ionomer-polyamide blend/polyamide copolymer

[0118] Ionomer (clear)/ionomer (pigmented)/tie layer/thermoplasticpolyolefin,

[0119] Ionomer/ionomer (pigmented)/tie layer/polyester copolymer,

[0120] Ionomer/ionomer (pigmented)/tie layer/recycle/tie layer/polyestercopolymer,

[0121] Ionomer/polyamide (pigmented)/tie layer/polyester, and

[0122] Ionomer/polyamide (pigmented)/tie layer/recycle/polyestercopolymer.

[0123] The decorative sheet may be adhered to a wide variety ofsubstrates to provide a high quality surface appearance, such as onesuitable for interior or exterior automotive parts or other panels. Itmay be used as decorative “thin” surface layer on “thick part” plasticsubstrates that can be subsequently thermoformed into an article.

[0124] Pigmented ionomer-polyamide blend and clear ionomer over apigmented substrate can provide valuable surface attributes for plasticparts, especially those that are now painted.

[0125] Optionally, pigment and/or flake particles may be included in thesurface layer or other layers in the case of a multilayer sheet process.In the case of an ionomer sheet construction, the ionomer can be coatedor laminated onto a patterned or designed film or sheet with the designor pattern showing through.

[0126] The high temperature properties of the ionomer-polyamide blendare sufficient to permit OEM Painting of molded parts without the needfor special jigs or hangers to maintain part shape during the bake step.

Shaped Article Forming Process

[0127] Shaped articles employing the decorative thermoplastic sheet ofthe present invention can be made by processes known in the artincluding injection cladding, compression molding and directthermoforming. The decorative thermoplastic sheet can also be laminatedonto a substrate to form an article.

[0128] A particularly useful method is injection cladding such asdescribed in U.S. Pat. No. 5,725,712 (incorporated herein by reference,see columns 16 through 20). The decorative thermoplastic sheet orco-extruded sheet can be back-filled with a wide variety of backfillmaterials. The flat sheet, preferably preheated, can be moved directlyinto an injection cladding mold for back-filling without thermoformingthe sheet first. By preheating, deep-draw shapes can be made withoutcreasing problems.

[0129] Direct thermoforming is particularly useful when the sheet beingthermoformed by itself is sufficiently thick to provide stiffness andrigidity needed by the article. Particularly useful for making suchdirectly thermoformed articles are co-extruded sheets with surfacematerials of ionomer or ionomer-polyamide blend.

[0130] A relatively thin (typically, 15-50 mils) decorative sheet can bethermoformed into a mold's shape and inserted into an injection mold orsheet molding compound (SMC) compression mold for cladding in a two stepprocess.

[0131] When using the decorative sheet made from ionomer, it has beenfound that it is not necessary to maintain the gloss of the sheet fromstart to finish, as it is in “paint film” systems. Instead, the surfacegloss of ionomers with a low temperature softening point can be improvedin final back-filling step as the film contacts the polished surface ofthe injection molding tool in the back-filling step. This propertyovercomes skin handling mars, reduces skin sheet handling costs andprovides for a more flexible and robust process. Preferably, thetemperature of the injection molding tool should be from about 10 toabout 50° C. The temperature of the back-filling molten polymer shouldbe sufficiently high to soften the ionomer or ionomer-polyamide skin sothat it conforms well to the mold and picks up a high gloss.

Shaped Plastic Article

[0132] The thermoformable skin discussed above can be formed into ashaped polymer article with the decorative skin on the outer surfacethereof. Shaped articles of this invention include automobile bodypanels, mirrors, accent pieces, grills, hoods, sport utility vehiclebody panels, appliance panels and the like. The shaped polymer articlesof this invention particularly are ones presenting a high qualitysurface appearance comparable to a high quality automotive paint finish.They exhibit high gloss, low gloss, or textured appearance and improvedmar resistance. These molded articles typically exhibit DOI's of atleast 80 and frequently as high as 90 to 95. Solid and metallic colorscan be incorporated and parts can be painted.

[0133] Shaped articles employing the thermoformable sheet of thisinvention as a top layer, particularly with the addition of standard UVstabilizers for the ionomer and ionomer-polyamide blend, exhibit goodweatherability, being particularly stable when exposed to ultravioletlight for extended periods of time. These articles exhibit the low colorshift, measured using, for example, the CIE 1976 (CIE LAB) color scale,needed for molded parts used in exterior applications. They exhibit ΔEcolor shift values of less than about 3 (a level considered as suitablefor exterior automotive applications) when exposed to 2500kilojoules/square meter in a Xenon-arc weatherometer (SAE J1960).Improved automobile fascia having DOI of at least 80 and superior marresistance can be made employing the thermoformable sheet of thisinvention.

Ionomer

[0134] The ionomers of the present invention are derived from directcopolymers of ethylene and α,β ethenically unsaturated C₃-C₈ carboxylicacid (“ethylene-acid copolymers”) by neutralization with metal ions. By“direct copolymer”, it is meant that the copolymer is made bypolymerization of monomers together at the same time, as distinct from a“graft copolymer” where a monomer is attached or polymerized onto anexisting polymer chain. Methods of preparing such ionomers are wellknown and are described in U.S. Pat. No. 3,264,272 (incorporated hereinby reference). Preparation of the direct ethylene-acid copolymers onwhich the ionomers are based is described in U.S. Pat. No. 4,351,931(incorporated herein by reference). Ethylene-acid copolymers with highlevels of acid are difficult to prepare in a continuous polymerizerbecause of monomer-polymer phase separation. This difficulty can beavoided however by use of “cosolvent technology” as described in U.S.Pat. No. 5,028,674 (incorporated herein by reference) or by employingsomewhat higher pressures than those at which copolymers with lower acidcan be prepared.

[0135] The ethylene-acid copolymers used to make the ionomeric copolymerof this invention can be E/X/Y copolymers where E is ethylene; X is asoftening comonomer and Y is the α,β-ethenically unsaturated C₃-C₈carboxylic acid, particularly acrylic or methacrylic acid. Preferably,however, the ethylene-acid copolymer is a dipolymer (no softeningcomonomer). The preferred acid moieties are methacrylic acid and acrylicacid.

[0136] By “softening”, it is meant that the polymer is made lesscrystalline. Suitable “softening” comonomers (X) are monomers selectedfrom alkyl acrylate, and alkyl methacrylate, wherein the alkyl groupshave from 1-12 carbon atoms which, when present, may be up to 30(preferably up to 25, most preferably up to 12) wt.% of theethylene-acid copolymer.

[0137] Preferred ethylene-acid dipolymers are ethylene-acrylic acid andethylene-methacrylic acid. Specific other copolymers includeethylene—n-butyl acrylate—acrylic acid, ethylene—n-butylacrylate—methacrylic acid, ethylene—iso-butyl acrylate—methacrylic acid,ethylene—iso-butyl acrylate—acrylic acid, ethylene—n-butylmethacrylate—methacrylic acid, ethylene—methyl methacrylate—acrylicacid, ethylene—methyl acrylate—acrylic acid, ethylene—methylacrylate—methacrylic acid, ethylene—methyl methacrylate—methacrylicacid, and ethylene—n-butyl methacrylate—acrylic acid (where the dashrepresents comonomers).

[0138] The mole percent acid moiety (i.e., mole percent of carboxylgroup, —COOH, relative to an elemental mole basis) in the ethylene-acidcopolymer prior to neutralization in the ionomer employed by itself as alayer preferably is 0.54 to 1.26%, alternately 0.68 to 1.11%, or 0.82 to0.96% and the degree of neutralization preferably is 30 to 100%,alternately 40 to 80%, or 45 to 70%. On a polymer mole basis, the molepercent acid moiety in the ethylene-acid copolymer prior toneutralization in the ionomer employed by itself as a layer preferablyis 3.3 to 8.3%, alternatively 4.1 to 7.2%, or 4.6 to 6.2% and the degreeof neutralization preferably is 25 to 100%, alternatively 35 to 80%, or45 to 70%. Higher percent acid and higher neutralization is preferred toobtain improved mar-resistance and clarity or wet look in clear ionomerconstructions for decorative surfaces. For ethylene—methacrylic-acidcopolymers, the weight percent methacrylic acid is preferably greaterthan 8%, more preferably greater than 10%, alternatively greater than12%, preferably in the range of 13-19%. For ethylene—acrylic acidcopolymers, the percent acrylic acid is preferably greater than 7%, morepreferably greater than 9%, alternatively greater than 10%, preferablyin the range of 11-17%. A blend of ionomers can also be employed toenhance mar performance and yet maintain adequate temperatureresistance.

[0139] While the neutralizing agent (e.g., zinc oxide, magnesium oxide,and calcium oxide) can be added in solid form, it preferably is added asa concentrate in an ethylene-acid copolymer carrier. This concentrate ismade by carefully selecting the ethylene-acid copolymer and the blendingconditions to assure that the neutralizing agent does not significantlyneutralize the carrier. This neutralizing concentrate can also containsmall amounts (up to about 2 wt.%) of one or more salts of the metalcations (e.g. acetates and stearates). The acid copolymer can beneutralized with a mixture of ions by using different neutralizingagents which can provide enhanced mar resistance.

[0140] The ionomers of this invention are clear and have low hazelevels. They also have outstanding melt strength at thermoformingtemperatures employed with these skins allowing large parts with deepdraws to be formed.

[0141] The ionomer layer(s) can degrade and crack during UV exposure.Suitable UV additives such as hindered amines light stabilizers, UVlight absorbers along with other suitable stabilizers can increase thelayers durability and appearance to withstand extended outdoor exposure.

[0142] The surface ionomer layer attracts dust due to electrostaticsurface charges. Adding anti-stat additives to the top layer and thesecond layer can reduce dust sticking which enhances sheet processingand reduces the potential for surface imperfections in the finalarticle.

Ionomer-polyamide Blend

[0143] The ionomer-polyamide blend used in the present invention is oneor more polyamides with one or more ionomers, wherein the ionomer isdispersed in a continuous (or co-continuous) polyamide phase. Itpreferably is made by the process taught in U.S. Pat. No. 5,866,658(incorporated herein by reference).

[0144] The ionomer(s), as more fully set forth above, are preferablydirect copolymer(s) comprising ethylene and α,β-ethenically-unsaturatedC₃-C₈ carboxylic acid wherein the average acid of the directcopolymer(s) prior to neutralization is present in a high percentage andwherein 55 to 100 mole percent of the acid is neutralized with one ormore metal cations. Preferably the unsaturated C₃-C₈ carboxylic acid ismethacrylic acid making up 15 to 25 weight percent of the directcopolymer of ethylene and methacrylic acid or acrylic acid making up 14to 25 weight percent of the direct copolymer of ethylene and acrylicacid. Preferably the metal cation used to neutralize the carboxylic acidalso interacts with the amide links of the polyamide. Preferably zinc isused.

[0145] The ethylene-acid copolymers used to make the ionomericcopolymers employed in the ionomer-polyamide blends of this inventionhave the acid moiety present in a high amount. The amount that will beconsidered as “high” will depend on which acid moiety is employed,particularly the molecular weight of the acid moiety. In the case ofethylene—methacrylic acid, the preferred acid level is 13 to 25,(preferably 14 to 25, more preferably 15 to 22) wt.% of the copolymer.In the case of ethylene—acrylic acid, the preferred acid level is 8 to25, (preferably 9 to 25, more preferably 10 to 22) wt.% of thecopolymer. Particularly in view of the disclosures herein, one skilledin the art will be able to determine the “high” acid levels for otheracid moieties that are needed to get the desired gloss levels andabrasion resistance.

[0146] It will be recognized that it is possible to blend more than onecopolymer, the acid level of any one or more being outside the “high”range of the invention, to obtain an average acid level prior toneutralization that is within the preferred high percentage acid levels.Preferably, in the case of blends, the weight percent acid in each acidcopolymer from which the ionomer components are derived should be closeto the preferred range, and most preferably they should be within thisrange.

[0147] The acid moiety is preferably highly neutralized by metalcations, particularly monovalent and/or divalent metal cations. It ispreferable to neutralize with metal cations that are compatible with thenylon, that is, with cations that also interact with the amide links ofthe polyamide. Preferred metal cations include sodium, lithium,magnesium, calcium, and zinc, or a combination of such cations. Blendsof cations are most preferred. Potassium and sodium are poor choices.Magnesium and calcium preferably are used in combination with zinc.

[0148] The polyamide component, as more fully set forth below,preferably has a viscosity under melt-blend conditions that is highenough to provide the mechanical properties but low enough to create thedesired phase relationship. The polyamides comprise semicrystallinepolyamides, preferably polycaprolamide (nylon 6). It may also comprise ablend of semicrystalline and amorphous polyamides with the amorphouspolyamide fraction up to 70% based on total polyamide weight. Anamorphous polyamide that can be used ishexamethylenediamine—isophthalamide—terephthalamide terpolymer.

[0149] Preferably, the blend is 60 to 40 (more preferably 50 to 45, also60 to 55) wt.% ionomer and 40 to 60 (more preferably 50 to 55, also 40to 45) wt.% polyamide (percentages being based on total ionomer andpolyamide). Preferably, the ionomer is dispersed in a reasonably uniformmanner as small, essentially spherical particles for the most part withaverage diameter of preferably about 0.1 to about 0.2 μm in a continuouspolyamide phase. Also, the ionomer preferably is dispersed as oblong andcurvilinear or ellipsoid shaped particles for the most part with anaverage cross-sectional diameter (minor axis length) of about 0.1 toabout 0.2 μm in a co-continuous polyamide phase. The average ratio ofmajor axis length to minor acid length can be about 2 to about 10 orgreater.

[0150] The blend may also contain components such as ultraviolet (UV)light stabilizers, antioxidants and thermal stabilizers, pigments anddyes, fillers, anti-slip agents, plasticizers, nucleating agents, andthe like for both polyamide and ionomer. Preferably, these componentsare present in amounts of about 1 to about 3 (preferably about 1.5 toabout 3) parts per hundred parts by weight of the ionomer-polyamideblend, but may be present in lower or higher levels.

[0151] To achieve the desired morphology (ionomer dispersed incontinuous or co-continuous nylon phase) using the preferred process,the ionomer must have a sufficiently high acid level and be neutralizedto a sufficiently high level to attain a viscosity greater than that ofthe nylon. The polyamide should have a viscosity higher than that of theethylene-acid copolymer or ionomer at low neutralization levels, butshould be less than the ionomer at high neutralization levels.Preferably, it is made by first blending a partially neutralized, lowerviscosity ethylene-acid copolymer with a sufficiently high acid levelinto the nylon and then further neutralizing sufficiently to raise theionomer viscosity while melt blending under intense mixing conditions.Non-neutralized (or lowly neutralized), high-acid ethylene-acidcopolymer can be melt blended with the polyamide with all of itsneutralization being effected during the melt blending. At the highdegree of neutralization, the viscosity of the ionomer will exceed thatof the polyamide at processing conditions.

[0152] The preferred level of neutralization will depend on theethylene-acid copolymers employed and the properties desired.Neutralization in the blend should be sufficient to raise the melt index(MI) of the ionomer in the blend, measured as grams of ionomer exiting a0.0823 inch orifice in ten minutes (gn/10 min) at 190° C. with 2160 gramweight applied force (ASTM D-1238 condition E), to such a level that, ifthe ionomer alone (not in the nylon blend) were neutralized to thatlevel, there would be very low to essentially no flow (preferably lessthan about 0.2 grams/10 minutes). For example, for an ethylene-aciddipolymer of ethylene and 19 wt.% methacrylic acid, the following MIvalues result when the dipolymer is neutralized to the degree indicated:% Neutralization MI (gm/10 min)  0 60    ˜38 2.7  ˜52-58 0.71 ˜60 0.17˜67 0.13 ˜90 0 to 0.015

[0153] In this case the percent neutralization should be about 60% orgreater since the grams of ionomer exiting the orifice is less than 0.2grams per 10 minutes. One skilled in the art can easily determine thepreferred percent neutralization for other ionomers. Preferably in thefinal melt blend with polyamide, the mole percent of acid neutralized is65 to 100%, more preferably 75 to 100%, alternatively 75 to 85%.

[0154] The level of acid and the degree of neutralization can beadjusted to achieve the particular properties desired. Gloss is enhancedby raising the average acid level. High neutralization yields harder,glossier products while more moderate neutralization yields tougherproducts.

Polyamide

[0155] Semicrystalline polyamides can be used in the ionomer-polyamideblends of the present invention. The term “semicrystalline polyamide” iswell known to those skilled in the art. Semicrystalline polyamidessuitable for this invention are generally prepared from lactams or aminoacids or from condensation of diamines such as hexamethylene diaminewith dibasic acids such as sebacic acid. Copolymers and terpolymers ofthese polyamides are also included. Preferred semicrystalline polyamidesare polycaprolamide (nylon 6), polyhexamethylene adipamide (nylon 6,6),most preferably nylon 6. Other semicrystalline polyamides useful in thepresent invention include nylon 11, nylon 12, nylon 12,12 and copolymersand terpolymers such as nylon 6/6,6, nylon 6/6,10, nylon 6/12, nylon6,6/12, nylon 6/6,6/6,10 and nylon 6/6T.

[0156] Amorphous polyamides can be substituted for some of thesemicrystalline polyamide to raise the glass transition temperature (Tg)of the nylon phase and to lower the temperature that this material canbe thermoformed at. Up to about 70 wt.%, preferably up to about 25-60wt.%, of the polyamide phase can be amorphous polyamides. The term“amorphous polyamide” is well known to those skilled in the art.“Amorphous polyamide,” as used herein, refers to those polyamides whichare lacking in crystallinity as shown by the lack of an endothermcrystalline melting peak in a Differential Scanning Calorimeter (“DSC”)measurement (ASTM D-3417), 10° C./minute heating rate.

[0157] Examples of the amorphous polyamides that can be used includehexamethylenediamine isophthalamide, hexamethylenediamineisophthalamide/terephthalamide terpolymer, having iso/-terephthalicmoiety ratios of 100/0 to 60/40, mixtures of 2,2,4- and2,4,4-trimethylhexamethylenediamine terephthalamide, copolymers ofhexamethylene diamine and 2-methylpentamethylenediame with iso-orterephthalic acids, or mixtures of these acids. Polyamides based onhexamethylenediamine iso/terephthalamide containing high levels ofterephthalic acid moiety may also be useful provided a second diaminesuch as 2-methyldiaminopentane is incorporated to produce a processibleamorphous polymer. Amorphous polyamides may contain, as comonomers,minor amounts of lactam species such as caprolactam or lauryl lactam,even though polymers based on these monomers alone are not amorphous aslong as they do not impart crystallinity to the polyamide. In addition,up to about 10 wt. % of a liquid or solid plasticizer such as glycerol,sorbitol, mannitol, or aromatic sulfonamide compounds (such as“Santicizer 8” from Monsanto) may be included with the amorphouspolyamide.

[0158] The amorphous polyamide may be a blend of ethylene vinyl alcoholand amorphous nylon in which the polyamide component comprises about 5to about 95 wt. % of the total composition of EVOH plus polyamide,preferably about 15 to about 70 wt. %, and most preferably about 15 toabout 30 wt. %.

Backfill Material

[0159] Backfill materials may include a wide variety of polymers. Thesematerials include thermoplastic polyolefins (TPO), polyesters (PET),sheet molding compounds (SMC), acrylonitrile butyl styrene (ABS),polyvinyl chloride (PVC), polystyrene (PS), polyurethane (PU),Polyethylene including low density polyethylene (LDPE), linear lowdensity polyethylene (LLDPE), or high density polyethylene (HDPE), andothers materials. Backfill materials can also incorporate scrap materialrecycled from the sheet making process.

[0160] In injection cladding, alternative backfilling processes can beused with backfill material such as foam generation or gas injectionduring the backfill injection operation. The high gloss decorativesurface can be maintained with these alternative backfill processes orwith fillers in the backfill material.

[0161] Through proper skin sheet design, surface defects from glass orother fillers in the backfill material can be avoided. Glass typefiller, typically used for stiffening, often provides a poor surfacefinish due to glass showing through at the surface. The use of this skinfilm can provide an article which has glass in the backing material forstiffening yet with a surface free of glass surface imperfections.

Tie Layer

[0162] Tie layers useful in the present invention include those filmswell known in the art for forming melt-bond layers that adhere to thefilms or substrates to which they come in contact. Co-extrudableadhesives based on blends of various polyethylenes are well known. Forexample blends of polyethylene, ethylene/alpha-olefin copolymers, polarethylene co- or terpolymers and/or ethylene elastomers or rubbers whichare adhesive to the ionomer, or an ethylene copolymer which is adhesiveto the ionomer-nylon alloy, such as ethylene vinyl acetate (EVA),ethylene (meth)acrylate copolymers (EA and EMA), and ethylene butylacrylate copolymers (EBA). Others include polypropylene (PP) and maleicanhydride modified polymers including polypropylenes which are adhesiveto TPO or PP and ionomer-polyamide blends, or PET or PETG copolymerresins which are adhesive to higher copolymer containing ethylenecopolymers, or ionomer-polyamide blends which are adhesive to nyloncopolymers such as Elvamide®. Further ethylene based polymer blends,especially copolymers containing anhydride grafts demonstrate improvedadhesion to the ionomer-nylon alloy.

[0163] Adhesive layers provide delamination resistance between thesurface layers and subsequent functional layers during processing andend-use.

Ethylene Polar Copolymers

[0164] The ethylene polar copolymers useful in the present inventioninclude generally any polymer derived from copolymerizing ethylene andone or more polar comonomers having and acid or acid relatedfunctionality. As such there role as a polymeric layer in a multilayerfilm or sheet may be similar to the above described tie layer. Theethylene polar copolymers include polymer made by directcopolymerization or by grafting and the like. The acid or acid relatedfunctionality typically involves comonomer containing the carboxylgroup, esters of the carboxyl group, acid anhydride and the likeincluding vinyl carboxylates such as vinyl acetate. Thus the ethylenepolar copolymer includes by way of example (but not limited thereto)polymers such as ethylene copolymers containing maleic anhydride,acrylic acid, methacrylic acid, and various esters of (meth)acrylicacid; i.e., (meth)acrylates. The ethylene polar copolymers also includethe EVA type copolymers.

Other Components

[0165] Additives normally compounded into plastics may be included inthe blend, for example, ultra-violet (UV) stabilizers, UV absorbers,antioxidants, thermal stabilizers, anti-stat additives, processing aids,pigments and the like. When included, these components are preferablypresent in amounts of about 1 to about 3 (preferably about 1.5 to about3) parts per hundred parts by weight of the ionomer-polyamide blend butmay be present in lower or higher amounts. These components arepreferably present in amounts of about 0.3 to about 3 (preferably about0.6 to about 1.3) parts per hundred parts by weight in the ionomer onlysurface layer.

[0166] Of particular importance if the part is to be exposed toultraviolet (UV) light is the inclusion of one or more UV stabilizersfor the nylon and for the ionomer. Typically useful UV stabilizersinclude: benzophenones such as hydroxy dodecyloxy benzophenone,2,4-dihydroxybenzophenone, hydroxybenzophenones containing sulfonicgroups and the like; triazoles such as2-phenyl-4-(2′,2′-dihydroxylbenzoyl)-triazoles; substitutedbenzothiazoles such as hydroxy-phenylthiazoles and the like; triazinessuch as 3,5-dialkyl-4-hydroxyphenyl derivatives of triazine, sulfurcontaining derivatives of dialkyl-4-hydroxy phenyl triazines, hydroxyphenyl-1,3,5-triazine and the like; benzoates such as dibenzoate ofdiphenylol propane, tertiary butyl benzoate of diphenylol propane andthe like; and others such as lower alkyl thiomethylene containingphenols, substituted benzenes such as1,3-bis-(2′-hydroxybenzoyl)benzene, metal derivatives of3,5-di-t-butyl-4-hydroxy phenyl propionic acid, asymmetrical oxalicacid, diarylamides, alkylhydroxy-phenyl-thioalkanoic acid ester, andhindered amines of bipiperidyl derivatives.

[0167] Preferred UV stabilizers and absorbers, all available from CibaGeigy, are Tinuvin®234(2-(2H-benzotriazol-2-yl)-4,6-bis(1-methyl-1-phenylethyl)phenol),Tinuvin®327 (2-(3′,5′-di-tert-butyl-2′-hydroxyphenyl)-5chlorobenzotriazole), Tinuvin®328(2-(2′hydroxy-3′,5′-di-tert-amylphenyl)benzotriazole), Tinuvin®329(2-(2′-hydroxy-5′-tert-octylphenyl)benzotriazole), Tinuvin (®765(bis(1,2,2,6,6-pentamethyl-4-piperidinyl) sebacate), Tinuvin®770(bis(2,2,6,6-tetramethyl-4-piperidinyl) decanedioate), Tinuvin® 928,(Chimassorb 2020 (1,6-Hexanediamine, N,N′-bis(2,2,6,6-tetramethyl-4-piperidinyl)-polymer, Chimassorb 119(1,3,5-Triazine-2,4,6-triamine,N,N′″-[1,2-ethane-diyl-bis[[[4,6-bis-[butyl(1,2,2,6,6-pentamethyl-4-piperidinyl)amino]-1,3,5-triazine-2-yl]imino]-3,1-propanediyl]]bis[N′,N″-dibutyl-N′,N″-bis(1,2,2,6,6-pentamethyl-4-piperidinyl)-andChimassorb™944(N,N′-bis(2,2,6,6-tetramethyl-4-piperidinyl)-1,6-hexanediamine polymerwith 2,4,6-trichloro-1,3,5-triazine and2,4,4-trimethyl-1,2-pentanamine).

[0168] Preferred thermal stabilizers, all available from Ciba Geigy, areIrganox®259 (hexamethylenebis(3,5-di-tert-butyl-4-hydroxyhydrocinnamate), Irganox®1010(3,5-bis(1,1 -dimethylethyl)-4-hyroxybenzenepropanoic acid,2,2-bis[[3-[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]-1-oxopropoxy]methyl]1,3-propanediylester), Irganox®1076 (octadecyl3,5-di-tert-butyl-4-hydroxyhydrocinnamate), Iragnox®1098(N,N′-hexamethylene bis(3,5-di-tert -butyl-4-hydroxyhydrocinnamamide),Irganox®B215 (33/67 blend of Irganox®1010 withtris(2,4-di-tert-butylphenyl)phosphite), Irganox®B225 (50/50 blend ofIrganox®1010 with tris(2,4-di-tert-butylphenyl)phosphite), andIrganox®B1171 (50/50 blend of Irganox®1098 with tris(2,4-di-tert-butylphenyl)phosphite).

[0169] Preferred processing aids include aluminum distearate and zincstearate, particularly zinc stearate.

[0170] Pigments include both clear pigments such as inorganic siliceouspigments (silica pigments for example) and conventional pigments used incoating compositions. Conventional pigments include metallic oxides suchas titanium dioxide, and iron oxide; metal hydroxides; metal flakes suchas aluminum flake; chromates such as lead chromate; sulfides; sulfates;carbonates; carbon black; silica; talc; china clay; phthalocyanine bluesand greens, organo reds; organo maroons and other organic pigments anddyes. Particularly preferred are pigments that are stable at hightemperatures.

[0171] Pigments are generally formulated into a millbase by mixing thepigments with a dispersing resin that may be the same as or compatiblewith the material into which the pigment is to be incorporated. Pigmentdispersions are formed by conventional means such as sand grinding, ballmilling, attritor grinding or two-roll milling.

[0172] Other additives, while not generally needed or used, such asfiber glass and mineral fillers, anti-slip agents, plasticizers,nucleating agents, and the like, can be incorporated.

[0173] Preferably, the mixing and the degree of neutralization for theionomer-polyamide blend should be sufficient to bring about the phaseinversion (higher volume percent ionomer dispersed in the continuous orco-continuous nylon phase) in the mixing equipment. It should berecognized, however, that full inversion may not occur in the mixingequipment but may result from further working of the blend in injectionmolding operations for forming plaques and the like.

Tests Used in the Examples

[0174] The differential scanning calorimeter (DSC) cooling exotherm caneasily and quickly be determined and is a useful indicator of morphologyand the sufficiency of mixing conditions for the desired morphology inthe ionomer-polyamide blend. The DSC cooling exotherm will differdepending on the nylon used, but can easily be determined by one skilledin the art. Preferably, the DSC cooling exotherm when using nylon 6should be 160° C. to 180° C. when cooling is carried out at a rapid rate(e.g. 30° C. min.). The presence of this exotherm indicates that thedesired phase relationship has been achieved. Higher amorphous polyamidefractions in the ionomer-polyamide blend will reduce this exotherm inenthalpy and temperature.

[0175] Tensile tests are also useful indicators of the ionomer-polyamideblend product morphology. When the morphology is correct, the ratio ofTension at Break (T_(B)) at room temperature (23° C.) to T_(B) atelevated temperature (150° C.) preferably is less than about 12 to 15.

EXAMPLES

[0176] The following Examples show various aspects of this invention.

[0177] The multilayer sheets in the examples were made on a co-extrusionline that has 4 extruders and 5 layer capability. The co-extruder lineused was configured as described above with a co-extrusion feed blockfor the purpose of combining the flows into contacting layers. The flowswere routed within the feed block so as to combine the layers prior toexiting the feed block and going into a coat hanger type extrusion die.The combined layers exiting the die flow as a molten curtain verticallyonto a metal roller just prior to a second highly polishedcounter-rotating roll forming a nip with the first roll. The sheetcontacts the highly polished surface for approximately ½ of itscircumference prior to releasing the solidifying plastic to a third rollin the takeoff roller system. The sheet is subsequently taken throughanother nip system between rollers, which pulls the sheet in the system.The sheet is subsequently rolled onto a core creating a roll of sheet orcut to length and stacked.

Example 1

[0178] A 2-layer structure of Surlyn®9910Bexloy® W720, using a clearSurlyn® top layer and a pigmented Bexloy® W720 backing layer was madeemploying a co-extrusion line. Surlyn®9910 is a 15 wt % acid (EMAAcopolymer) which is approximately 50% neutralized. Bexloy® W720 is apolyethylene ionomer blend in which the polyethylene is a HDPE and theionomer is an EMAA copolymer with 10 wt % acid that is neutralized toapproximately 70%. The blend is intensively mixed.

[0179] Table 1 shows the ingredients feeding the 3 extruders being usedin this case. These ingredients can be individually fed to each extruderor a pre-mixed blend of these components can be fed. TABLE 1 Extruder AExtruder B Extruder C Sheet Layer Layer 1 (top) Layer 3 Layer 2 ExtruderDiameter 2.5 2 1.5 (inches) Materials: Surlyn ® 9910 99% Bexloy ® W72095% 95% UV Processing  1% Additives Pigment Concentrate  5%  5%

[0180] TABLE 2 (equipment processing conditions) Temp Setpoint Profiles:(° F.) Extruder A Extruder B Extruder C Rear Feed Extruder Zone 1 305400 400 Mid Rear Zone 2 325 425 425 Mid Front Zone 3 350 450 450 FrontZone 4 360 475 475 Front Zone 5 375 505 505 Front Zone 6 380 None NoneTransfer Pipes 380 505 505 Feedblock 505 Extruder screw rpm's:  15  65 60 Die (left/center/right) 500/505/500 Feed block plug ID BBCAA Takeoff roll temperatures 70° F.

[0181] The 2 material flows originating in the extruders forms a 2 layersheet. Since 2 extruders are being fed the same materials, the layerthickness in this case are 6 mil for extruder A and 27 mil for thecombined flows from extruders B & C.

[0182] This sheet can be thermoformed on a male tool with the Bexloy®W720 surface contacting the forming tool. In forming, the Surlyn®surface might change due to internal stresses in the sheet resulting inorange peel or a mottle appearance in the formerly glossy surface. Thisformed sheet can then be inserted into an injection tool for injectioncladding. Bexloy® W720 would be a suitable backfilling material whichcan be injected onto the Bexloy® W720 side of the formed skin. Ininjection cladding, the Surlyn® surface exposed to a polished tool willsoften and form to the tool surface enhancing the glossy appearance inthe cladded part.

Example 2

[0183] A 3 layer structure of Surlyn®99910 (clear)/Surlyn®9910(pigmented)/Bexloy® W720, using a clear Surlyn® top layer, a pigmentedSurlyn® under layer and a Bexloy® W720 backing layer is made as inexample 1.

[0184] Table 3 shows the ingredients feeding the 3 extruders being usedin this case. These ingredients can be individually fed to each extruderor a pre-mixed blend of these components can be fed. TABLE 3 Extruder AExtruder B Extruder C Sheet Layer Layer 1 (top) Layer 3 Layer 2 ExtruderDiameter 2.5 2 1.5 (inches) Materials: Surlyn ® 9910 99% 90% Bexloy ®W720 100% UV Processing  1% Additives Pigment Concentrate 10%

[0185] TABLE 4 (equipment processing conditions) Temp Setpoint Profiles:(° F.) Extruder A Extruder B Extruder C Rear Feed Extruder Zone 1 375350 375 Mid Rear Zone 2 400 375 400 Mid Front Zone 3 400 400 400 FrontZone 4 400 500 400 Front Zone 5 400 510 400 Front Zone 6 400 None NoneTransfer Pipes 400 510 400 Feedblock 480 Extruder screw rpm's:  15 190150 Die (left/center/right) 410/510/510 Feed block plug ID BBCAA Takeoff roll temperatures 75° F. large, 70° F. small

[0186] The 3 material flows originating in the extruders form a 3 layersheet. The layer thicknesses in this case are 2.5 mil for extruder A(top layer), 8 mil for extruder C (middle) and 19 mils for extruders B(backing).

[0187] This sheet can be thermoformed on a male tool with the Bexloy®W720 surface contacting the forming tool similar to example 1 forming.Again in forming, the Surlyn® surface might change due to internalstresses in the sheet resulting in orange peel or a mottle appearance inthe formerly glossy surface. This formed sheet can then be inserted intoan injection tool for injection cladding. Bexloy® W720 would be asuitable backfilling material which can be injected onto the Bexloy®W720 side of the formed skin. In injection cladding, the Surlyn® surfaceexposed to a polished tool will soften and form to the tool surfaceenhancing the glossy appearance in the cladded part.

[0188] This example exhibits a clear Surlyn®/colored Surlyn® systemwhich provides the advantages of color matching in Surlyn® irrespectiveof the tie layer or backing material layer thickness or material. Inaddition, less pigment is required to provide a typical color matchsince Surlyn® has high clarity which is advantageous since less pigmentis needed to hide the opacity of less clear materials.

Example 3

[0189] A 4 layer structure of Surlyn®9910 (clear)/Surlyn®9910(pigmented)/co-extruded tie layer/Bexloy® W720, using a clear Surlyn®top layer, a pigmented Surlyn® under layer, a tie layer to improveadhesion between layers and a Bexloy® W720 backing layer was made withthe equipment and general approach of the preceding examples.

[0190] Table 5 shows the ingredients feeding the 3 extruders being usedin this case. These ingredients can be individually fed to each extruderor a pre-mixed blend of these components can be fed. TABLE 5 Ext. ALayer 1 Ext. B Ext. C Ext. D Sheet Layer (top) Layer 4 Layer 2 Layer 3Extruder Diameter 2.5 2 1.5 (inches) Materials: Surlyn ® 9910 99% 90%Bexloy ® W720 100% 75% LLDPE/25% EPDM 100% elastomer UV Processing  1%Additives Pigment Concentrate 10%

[0191] TABLE 6 (equipment processing conditions) Temp Setpoint Profiles:(° F.) Ext. A Ext. B Ext. C Ext. D Rear Feed Extruder Zone 1 375 350 375375 Mid Rear Zone 2 400 375 400 400 Mid Front Zone 3 400 400 400 400Front Zone 4 400 500 400 400 Front Zone 5 400 510 400 400 Front Zone 6400 none none None Transfer Pipes 400 510 400 400 Feedblock 480 Extruderscrew rpm's: Die (left/center/right) 410/510/510 Take off rolltemperatures 75° F. large, 70° F. small

[0192] The 4 material flows originating in the extruders form a 4 layersheet. The layer thicknesses in this case are 2.5 mil for extruder A(top layer), 8 mil for extruder C (middle) and 2 mils for extruder D and17.5 mils for extruder B (backing).

[0193] This sheet can be thermoformed on a male tool with the Bexloy®W720 surface contacting the forming tool similar to example 1 forming.Again in forming, the Surlyn® surface might change due to internalstresses in the sheet resulting in orange peel or a mottle appearance inthe formerly glossy surface. This formed sheet can then be inserted intoan injection tool for injection cladding. Bexloy® W720 would be asuitable backfilling material which can be injected onto the Bexloy®W720 side of the formed skin. In injection cladding, the Surlyn® surfaceexposed to a polished tool will soften and form to the tool surfaceenhancing the glossy appearance in the cladded part.

[0194] This example again exhibits a clear ionomer/ colored ionomersystem with its advantages mentioned previously.

Example 4

[0195] In manner similar to that described above, the followingmultilayered structures can be made:

[0196] For HDPE backing Ionomer/Ionomer (pigmented)/tie/HDPE

[0197] For TPO backing Ionomer/Ionomer (pigmented)/tie/TPO

[0198] For PE backing Ionomer/Ionomer (pigmented)/tie/PE

[0199] For nylon backing Ionomer/Ionomer (pigmented)/tie/nylon

[0200] For PET backing Ionomer/Ionomer (pigmented)/tie/PET

[0201] For ABS backing Ionomer/Ionomer (pigmented)/tie/ABS

[0202] In a similar fashion, the pigmented Ionomer layer can beeliminated if the tie and/or backing layers are pigmented.

[0203] Note: backing substrates may be added by filling, foaming,compression molding or by other processes.

Example 5

[0204] In a manner similar to that described above, ionomer-polyamidestructures can be made. The simplest of these structures will be of theform: ionomer-polyamide (pigmented)/tie layer/backing layer.

[0205] Examples with ionomer-polyamide surface layers with the followingstructures are:

[0206] For HDPE backing ionomer-polyamide (pigmented)//tie/HDPE

[0207] For TPO backing ionomer-polyamide (pigmented)//tie/TPO

[0208] For PE backing ionomer-polyamide (pigmented)//tie/PE

[0209] For nylon backing ionomer-polyamide (pigmented)//tie/nylon

[0210] For PET backing ionomer-polyamide (pigmented)//tie/PET

[0211] For ABS backing ionomer-polyamide (pigmented)//tie/ABS

[0212] Note: backing substrates may be filled, foamed, compressionmolded or applied by other processes.

[0213] For making a thermoplastic multilayer ionomer-polyamide/tie/TPOsheet, the following processing conditions can be used. Surlyn®Reflections SG201U white M261060 is an ionomer-polyamide blend withwhite color compounded into the resin, EP94592-116 adhesive layer isblend of polypropylene copolymer resin, anhydride modified polypropyleneand elastomer resin. Solvay TPO E1501 is a rubber modified polypropylenecopolymer. TABLE 7 Extruder A Extruder B Extruder C Sheet Layer Layer 1(top) Layer 3 Layer 2 Extruder Diameter (inches) 2.5 2 1.5 Materials:Surlyn ® Reflections 100% SG201U white M261060 EP94592-116 adhesive 100%layer Solvay TPO E1501 100% Layer Thickness (mils) 9 3 8

[0214] TABLE 8 (equipment processing conditions) Temp Setpoint Profiles:(° F.) Extruder A Extruder B Extruder C Rear Feed Extruder Zone 1 410400 350 Mid Rear Zone 2 450 450 350 Mid Front Zone 3 480 475 400 FrontZone 4 480 500 410 Front Zone 5 480 510 420 Front Zone 6 480 none noneTransfer Pipes 480 510 420 Feedblock 510 Extruder screw rpm's:  40  45 55 Die (left/center/right) 510/510/510 Feed block plug ID BBCAA Takeoff roll temperatures Primary Gloss roll: 180° F.; Secondary rolls: 120°F.

Example 6

[0215] In systems employing ionomer as the top layer and systemsemploying ionomer-polyamide blends, recycle may be incorporated. For thepurpose of this example, the Ionomer/Ionomer (pigmented) orIonomer-Polyamide-Blend (pigmented) top layers are referred to as the“Top system.” “Recycle+backing” represents that the recycle is includedin the backing material. Typical structures which might be employed withrecycle are as follows:

[0216] Top system/tie/recycle+backing

[0217] Top system/tie/recycle/tie

[0218] Top system/tie/recycle/tie/backing

[0219] Having thus described and exemplified the invention with acertain degree of particularity, it should be appreciated that thefollowing claims are not to be so limited but are to be afforded a scopecommensurate with the wording of each element of the claim andequivalents thereof.

I claim:
 1. A multilayer film or sheet comprising: a.) a firstco-extruded polymeric layer consisting essentially of ionomer; and b.)at least one co-extruded second polymeric layer selected from the groupconsisting of ionomer, ionomer-polyethylene blend, and ionomer-polyamideblend in contact with said first co-extruded polymeric layer.
 2. Amultilayer film or sheet of claim 1 further comprising at least oneadditional co-extruded third polymeric layer in contact with said secondco-extruded polymeric layer.
 3. A multilayer film or sheet of claim 1 or2 wherein said ionomer consisting essentially of a copolymer derivedfrom ethylene and α,β-ethenically unsaturated C₃ to C₈ carboxylic acidwherein said copolymer is partially neutralized with metal ions.
 4. Amultilayer film or sheet of claim 1 or 2 wherein said ionomer-polyamideblend consists essentially of one or more polyamide which forms acontinuous phase or co-continuous phase with one or more ionomerdispersed therein, said ionomer is present in the range from 60 to 40weight percent and said polyamide is present in the range from 40 to 60weight percent based on the total weight of ionomer and polyamide, saidionomer consisting essentially of a copolymer derived from ethylene andα,β-ethenically unsaturated C₃ to C8 carboxylic acid wherein saidcopolymer is partially neutralized with metal ions; wherein the averageacid content of copolymer prior to neutralization is present in asufficiently high percentage such that neutralization in the range of 55to 100 mole percent of the acid present at melt temperature with one ormore metal cations increases the viscosity of the ionomer above that ofthe polyamide.
 5. A multilayer film or sheet of claim 1 or 2 wherein oneor more of said co-extruded polymeric layers contain pigments, dyes,flakes, or mixtures thereof.
 6. A multilayer film or sheet of claim 1 or2 wherein said first co-extruded polymeric layer is clear and saidco-extruded second polymeric layer contains pigments, dyes, flakes, ormixtures thereof.
 7. A multilayer film or sheet comprising: a.) a firstco-extruded polymeric layer consisting essentially of ionomer; and b.)at least one co-extruded second polymeric layer consisting essentiallyof very low density polyethylene in contact with said first co-extrudedpolymeric layer.
 8. A multilayer film or sheet of claim 7 furthercomprising at least one additional co-extruded third polymeric layer incontact with said second co-extruded polymeric layer.
 9. A multilayerfilm or sheet of claim 7 or 8 wherein said ionomer consistingessentially of a copolymer derived from ethylene and α,β-ethenicallyunsaturated C₃ to C₈ carboxylic acid wherein said copolymer is partiallyneutralized with metal ions.
 10. A multilayer film or sheet of claim 7or 8 wherein one or more of said co-extruded polymeric layers containpigments, dyes, flakes, or mixtures thereof.
 11. A multilayer film orsheet of claim 7 or 8 wherein said first co-extruded polymeric layer isclear and said co-extruded second polymeric layer contains pigments,dyes, flakes, or mixtures thereof.
 12. A multilayer film or sheetcomprising: a.) a first co-extruded polymeric layer consistingessentially of ionomer; and b.) at least one co-extruded secondpolymeric sheet layer consisting essentially of ethylene polar copolymerin contact with said first co-extruded polymeric layer.
 13. A multilayerfilm or sheet of claim 12 further comprising at least one additionalco-extruded third polymeric layer in contact with said secondco-extruded polymeric layer.
 14. A multilayer film or sheet of claim 12or 13 wherein said ionomer consisting essentially of a copolymer derivedfrom ethylene and α,β-ethenically unsaturated C₃ to C₈ carboxylic acidwherein said copolymer is partially neutralized with metal ions.
 15. Amultilayer film or sheet of claim 12 or 13 wherein one or more of saidco-extruded polymeric layers contain pigments, dyes, flakes, or mixturesthereof.
 16. A multilayer film or sheet of claim 12 or 13 wherein saidfirst co-extruded polymeric layer is clear and said co-extruded secondpolymeric layer contains pigments, dyes, flakes, or mixtures thereof.17. A multilayer film or sheet comprising: a.) a first co-extrusionpolymeric layer consisting essentially of ionomer-polyamide blend; andb.) at least one additional co-extruded second polymeric layer incontact with said first co-extrude polymeric layer.
 18. A multilayerfilm or sheet of claim 17 wherein said ionomer-polyamide blend consistsessentially of one or more polyamide which forms a continuous phase orco-continuous phase with one or more ionomer dispersed therein, saidionomer is present in the range from 60 to 40 weight percent and saidpolyamide is present in the range from 40 to 60 weight percent based onthe total weight of ionomer and polyamide, said ionomer consistingessentially of a copolymer derived from ethylene and α,β-ethenicallyunsaturated C₃ to C₈ carboxylic acid wherein said copolymer is partiallyneutralized with metal ions; wherein the average acid content ofcopolymer prior to neutralization is present in a sufficiently highpercentage such that neutralization in the range of 55 to 100 molepercent of the acid present at melt temperature with one or more metalcations increases the viscosity of the ionomer above that of thepolyamide.
 19. A multilayer film or sheet of claim 17 or 18 wherein oneor more of said co-extruded polymeric layers contain pigments, dyes,flakes, or mixtures thereof.
 20. A multilayer film or sheet of claim 17or 18 wherein said first co-extruded polymeric layer contains pigments,dyes, flakes, or mixtures thereof.
 21. A multilayer film or sheet ofclaim 17 or 18 wherein said second co-extruded polymeric layer isselected from the group consisting of ionomer, ionomer-polyethyleneblend, ionomer-polyamide blend, very low density polyethylene, ethylenepolar copolymer, and blends thereof.
 22. A process for making shapedarticle having an ionomer or ionomer-polyamide blend as a top surfacecomprising the steps of: c.) positioning a monolayer sheet of ionomer orionomer-polyamide blend or a multilayer co-extruded sheet into a mold,wherein the thickness of said monolayer sheet or said multilayer sheetis from 8 to 60 mils and wherein said multilayer sheet comprises; i.) afirst co-extruded polymeric layer selected from the group consisting ofionomer and ionomer-polyamide blend; and ii.) at least one additionalco-extruded second polymeric layer in contact with said firstco-extruded polymeric layer; and d.) injection backfilling saidmonolayer sheet or multilayer co-extruded sheet with a suitablebackfilling material.
 23. A process according to claim 22 wherein saidmultilayer sheet comprises; (vii) a first co-extruded polymeric layerconsisting essentially of ionomer; (viii) a second co-extruded polymericlayer selected from the group consisting of ionomer andionomer-polyamide blend in contact with said first co-extrude polymericlayer; and (ix) at least one additional co-extruded third polymericlayer in contact with said second co-extrude polymeric layer.
 24. Aprocess of claim 22 or 23 wherein said ionomer consisting essentially ofa copolymer derived from ethylene and α,β-ethenically unsaturated C₃ toC₈ carboxylic acid wherein said copolymer is partially neutralized withmetal ions.
 25. A process of claim 22 or 23 wherein saidionomer-polyamide blend consists essentially of one or more polyamidewhich forms a continuous phase or co-continuous phase with one or moreionomer dispersed therein, said ionomer is present in the range from 60to 40 weight percent and said polyamide is present in the range from 40to 60 weight percent based on the total weight of ionomer and polyamide,said ionomer consisting essentially of a copolymer derived from ethyleneand α,β-ethenically unsaturated C₃ to C₈ carboxylic acid wherein saidcopolymer is partially neutralized with metal ions; wherein the averageacid content of copolymer prior to neutralization is present in asufficiently high percentage such that neutralization in the range of 55to 100 mole percent of the acid present at melt temperature with one ormore metal cations increases the viscosity of the ionomer above that ofthe polyamide.
 26. A process of claim 23 wherein said first co-extrudedpolymeric layer is clear and said co-extruded second polymeric layercontains pigments, dyes, flakes, or mixtures thereof.
 27. A process ofclaim 22, 23, or 26 further comprising the step of thermoforming saidmultilayer co-extruded sheet prior to positioning said sheet in a moldand injection backfilling.
 28. A process of claim 27 wherein the topsurface of said shaped article has a Distinctness of Image (DOI) of atleast 80 and a gloss that exceeds 60% at a 20 degree angle.
 29. Aprocess of claim 22, 23 or 26 wherein said suitable backfilling materialis selected from the group consisting of thermoplastic polyolefins,polyesters, sheet molding compounds (SMC), acrylonitrile butyl styrene,polyvinyl chloride, polystyrene, polyurethane, low density polyethylene,linear low density polyethylene, high density polyethylene, and mixturesthereof.
 30. A process of claim 22, 23, or 26 wherein said multilayersheet further comprises one or more co-extruded polymeric tie layersselected from the group consisting of: blends of polyethylene,ethylene/alpha-olefin copolymer, and ethylene elastomer; ethylene vinylacetate; ethylene (meth)acrylate copolymer; ethylene butyl acrylatecopolymer; polyethylene terephthalate and polyethylene terephthalateglycol copolymer resins; maleic anhydride modified polypropylene;copolymers containing anhydride grafts and mixture thereof.
 31. Aprocess of claim 22 wherein said multilayer sheet comprises co-extrudedpolymeric layers selected from the group consisting of: ionomermonolayer (clear or pigmented); ionomer-polyamide blend monolayer(pigmented); ionomer (clear)/polyethylene-ionomer blend (pigmented);ionomer (clear)/polyethylene-elastomer blend (pigmented); ionomer(clear)/ionomer (pigmented)/ethylene copolymer; ionomer (clear)/ionomer(pigmented)/very low density polyethylene; ionomer (clear)/ethylene acidcopolymer (pigmented)/very low density polyethylene (pigmented); ionomer(clear)/ethylene acid copolymer (pigmented)/very low densitypolyethylene/olefinic thermoplastic; ionomer (pigmented)/ionomer(pigmented)/ethylene acid copolymer; ionomer (pigmented)/ethylene acidcopolymer; ionomer (pigmented)/terpolymer ethylene-acid-acrylate(pigmented)/olefinic thermoplastic; ionomer (pigmented)/terpolymerethylene-acrylate-glycidal methacrylate (pigmented)/olefinicthermoplastic; ionomer (clear)/terpolymer ethylene-acid-acrylate(pigmented)/olefinic thermoplastic; ionomer (clear)/terpolymerethylene-acrylate-glycidal methacrylate (pigmented)/olefinicthermoplastic; ionomer (clear)/ionomer (pigmented)/terpolymerethylene-acrylate-glycidal methacrylate/olefinic thermoplastic; ionomer(clear)/ethylene-acrylate copolymer (pigmented)/ethylene copolymer;ionomer (clear)/ionomer (pigmented)/ethylene copolymer/polyethylene;ionomer (clear)/ionomer(pigmented)/ethylene copolymer/polyestercopolymer; ionomer (clear)/ionomer (pigmented)/polyamide (pigmented);ionomer (clear)/ionomer (pigmented)/tie layer (pigmented)/thermoplasticpolyolefin; ionomer (clear)/ionomer (pigmented)/tie layer/thermoplasticpolyolefin (pigmented); ionomer(clear)/ionomer(pigmented)/polyethylene-ionomer blend; ionomer(clear)/ionomer(pigmented)/tie/nitrile copolymer; ionomer-polyamideblend/tie/thermoplastic polyolefin; ionomer-polyamideblend/tie/polyester copolymer; ionomer-polyamide blend/tie/nitrilecopolymer; ionomer-polyamide blend/polyamide copolymer; ionomer(clear)/ionomer (pigmented)/tie layer/thermoplastic polyolefin;ionomer/ionomer (pigmented) tie layer polyester copolymer;ionomer/ionomer (pigmented)/tie layer/polyester copolymer,ionomer/polyamide (pigmented)/tie layer/polyester, ionomer/polyamide(pigmented)/tie layer/recycle/polyester copolymer; and ionomer/ionomer(pigmented)/tie layer/recycle/tie layer/polyester copolymer.
 32. Aprocess of claim 22, 23, or 26 wherein said multilayer sheet furthercomprises one or more additional co-extruded polymeric layers containingrecycled polymer.
 33. A process for making a thermoformed, multilayer,sheet-surfaced article comprising the steps of: c.) positioning amultilayer sheet into a mold, wherein the thickness of said multilayersheet is from 8 to 60 mils and wherein said multilayer sheet comprises;i.) a first co-extruded polymeric layer selected from the groupconsisting of ionomer and ionomer-polyamide blend; and ii.) at least oneadditional co-extruded second polymeric layer in contact with said firstco-extrude polymeric layer; and b.) raising the temperature of saidsheet sufficiently to soften said multilayer sheet; and c.) conformingsaid softened sheet to the contoured surface of a substrate in the mold.34. A process according to claim 33 wherein said multilayer sheetcomprises; (x) a first co-extruded polymeric layer consistingessentially of ionomer; (xi) a second co-extruded polymeric layerselected from the group consisting of ionomer and ionomer-polyamideblend in contact with said first co-extruded polymeric layer; and (xii)at least one additional co-extruded third polymeric layer in contactwith said second co-extrude polymeric layer.
 35. A process of claim 33or 34 wherein said multilayer sheet is pre-heated to soften said sheetprior to positioning into a mold.
 36. The process of claim 35 whereinthe mold has a deep draw.
 37. The process of claim 33 or 34 wherein theconforming of step (c) is at a sufficient pressure within the mold toform an article wherein the surface layer of said article closelyreplicates the surface finish of the mold.
 38. The process of claim 37wherein the mold is highly polished so as to provide a high glosssurface attribute on said article.
 39. The process of claim 37 whereinthe mold is textured so as to provide a textured surface on saidarticle.
 40. The process of claim 35 wherein the conforming of step (c)is at a sufficient pressure within the mold to form an article whereinthe surface layer of said article closely replicates the surface finishof the mold.
 41. The process of claim 40 wherein the mold is highlypolished so as to provide a high gloss surface attribute on saidarticle.
 42. The process of claim 40 wherein the mold is textured so asto provide a textured surface on said article.
 43. An article consistingessentially of a substrate to which a multilayer film or sheet isadhered, wherein said multilayer film or sheet comprises: a.) a firstco-extruded polymeric layer consisting essentially of ionomer; and b.)at least one co-extruded second polymeric layer selected from the groupconsisting of ionomer, ionomer-polyethylene blend, and ionomer-polyamideblend in contact with said first co-extruded polymeric layer.
 44. Aarticle of claim 43 wherein said multilayer film or sheet furthercomprises at least one additional co-extruded third polymeric layer incontact with said second co-extruded polymeric layer.
 45. An articleconsisting essentially of a substrate to which a multilayer film orsheet is adhered, wherein said multilayer film or sheet comprises: a.) afirst co-extruded polymeric layer consisting essentially of ionomer; andb.) at least one co-extruded second polymeric layer consistingessentially of very low density polyethylene in contact with said firstco-extruded polymeric layer.
 46. A article of claim 45 wherein saidmultilayer film or sheet further comprises at least one additionalco-extruded third polymeric layer in contact with said secondco-extruded polymeric layer.
 47. An article consisting essentially of asubstrate to which a multilayer film or sheet is adhered, wherein saidmultilayer film or sheet comprises: a.) a first co-extruded polymericlayer consisting essentially of ionomer; and b.) at least oneco-extruded second polymeric sheet layer consisting essentially ofethylene polar copolymer in contact with said first co-extrudedpolymeric layer.
 48. A article of claim 47 wherein said multilayer filmor sheet further comprises at least one additional co-extruded thirdpolymeric layer in contact with said second co-extruded polymeric layer.49. An article consisting essentially of a substrate to which amultilayer film or sheet is adhered, wherein said multilayer film orsheet comprises: a.) a first co-extrusion polymeric layer consistingessentially of ionomer-polyamide blend; and b.) at least one additionalco-extruded second polymeric layer in contact with said first co-extrudepolymeric layer.
 50. A article of claim 49 wherein said multilayer filmor sheet further comprises at least one additional co-extruded thirdpolymeric layer in contact with said second co-extruded polymeric layer.51. An article in any of claims 43-50 wherein the substrate is selectedfrom the group consisting of metal, polymer, and polymer composite. 52.An article in any of claims 43-50 wherein the substrate has a printeddesign or pattern and said multilayer film or sheet is clear.
 53. Anarticle in any of claims 43-50 wherein one or more of said co-extrudedpolymeric layers contain pigments, dyes, flakes, or mixtures thereof.